This Vienna bridge multi-band oscillator circuit was found in a 1974 Ferranti transistor manual. The circuit generates signals from 25 Hz to 1 MHz in 5 bands selected by the capacitors.
This circuit is from a July 1970 Radio Electronics magazine. The sensors are metal probes. The 18 V...
This commercial medium and short-wave radio was manufactured in Japan in the 60s. The circuit has...
General Electric suggests this circuit in an 80's documentation. The circuit makes use of PUTs...